Fair Value (Fair Value On Nonrecurring Basis) (Detail) (Fair Value, Measurements, Nonrecurring, USD $) In Millions, unless otherwise specified	12 Months Ended
	Jul. 28, 2012	Jul. 30, 2011	Jul. 31, 2010
Recognized Gain (Loss) for the Period
Fair Value Assets And Liabilities Measured On Nonrecurring Basis [Line Items]
Recognized (gain) loss for period	$ (434)	$ (273)	$ (137)
Recognized Gain (Loss) for the Period | Property Held For Sale
Fair Value Assets And Liabilities Measured On Nonrecurring Basis [Line Items]
Recognized (gain) loss for period	(413)	(38)	(86)
Recognized Gain (Loss) for the Period | Investments In Privately Held Companies
Fair Value Assets And Liabilities Measured On Nonrecurring Basis [Line Items]
Recognized (gain) loss for period	(23)	(10)	(25)
Recognized Gain (Loss) for the Period | Purchased Intangible Assets
Fair Value Assets And Liabilities Measured On Nonrecurring Basis [Line Items]
Recognized (gain) loss for period	(12)	(164)	(28)
Recognized Gain (Loss) for the Period | Manufacturing operations held for sale
Fair Value Assets And Liabilities Measured On Nonrecurring Basis [Line Items]
Recognized (gain) loss for period		(61)
Recognized Gain (Loss) for the Period | Assets
Fair Value Assets And Liabilities Measured On Nonrecurring Basis [Line Items]
Recognized (gain) loss for period	14		2
Net Carrying Value
Fair Value Assets And Liabilities Measured On Nonrecurring Basis [Line Items]
Property held for sale	63	20	25
Investments in privately held companies	47	13	45
Purchased intangible assets
Manufacturing operations held for sale		$ 167